Spot on!

This weeks headache.

A clue, its sister fly's regularly over my apartment??

Tiger moth.

Not a Tiger Moth, but on the right track.
Most of them built, had a radial engine??
She also served with Portugal & Taiwan ??

Another clue.
It was powered by 90 hp (67 kW) Wright-Gypsy or 130 hp (97 kW) Gypsy Major inline engine, built under license in ???????

Think I've got it, it's a Fleet Finch model 10G: http://en.wikipedia.org/wiki/Fleet_Finch

Well done Harry it is indeed.
Here's a link too the Finch at my local airfield - http://www.tigerboys.com/finch.html

And of course your prize.

This weeks headache??

Hey Duggy is that one of the Curtis Flying Boats ?